1

2

Sample of Lua Syntax (FOR loop):

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for i=1,10 do
    -- the first program in every language
    io.write("Hello world, from ",_VERSION,"!\n")
end

• For full description see: About.

3

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-- # MessageBox
--------------------------------------------------------
-- int MessageBox(
-- string msg, |= Message to display
-- string capition |= Capition of Box
-- );
-- Return Value:
-- if 1 the user click in OK or user close the box


-- # ShowContentPainel
-----------------------------------------------------------------
-- void ShowContentPainel(
-- bool bShow |= If true, the painel start opened, if false not.
-- );

-- # SetWindowStartSize
-----------------------------------------------------------------
-- void SetWindowStartSize(
-- number w, |= Start W size of window
-- number h, |= Start H size of window
-- );
-- Remarks:
-- if this function is not called, the default size is 800 x 600

-- # SetMinWindowSize
-----------------------------------------------------------------
-- void SetMinWindowSize(
-- number w, |= Minimum W size of window
-- number h, |= Minimum H size of window
-- );

-- # SetTitle
-----------------------------------------------------------------
-- void SetTitle(
-- string title |= Text that be title of window.
-- );

-- # Navigate
-----------------------------------------------------------------
-- void Navigate(
-- string url |= Url
-- );

-- # InsertItemInPainel
-----------------------------------------------------------------
-- void InsertItemInPainel(
-- string title, |= Text displayed in tree
-- string url, |= Url
-- number icon, |= Icon of item, the possible values 
                           ---are: 0 = BOOK, 1 = FILE, 2 = NETFILE
-- number id, |= Id of item, this has to be unique and start in 1
-- number idp |= Parent item, this is a ID of a item that is 
                                ---the parent or '0' for root item.
-- );
-- sample:
-- ICON BOOK / ID 1 / In ROOT
-- InsertItemInPainel("Trinity Systems", 
            "http://www.novaamerica.net/trinitysystems/", 0, 1, 0); 
-- ICON NETFILE / ID 2 / In ID1 (Trinity Systems)
-- InsertItemInPainel("Orion", 
       "http://www.novaamerica.net/trinitysystems/Orion", 2, 2, 1); 

-- # ExpandItemInPainel
------------------------------------------------------------------
-- void ExpandItemInPainel(
-- string id |= Id of item
-- );
-- Remarks:
-- This function need to be called after InsertItemInPainel's

4

1. The first thing to do is to build the DLL that contains Lua. (download Lua DLL demo project)
2. Link this in your project:
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   //
   // For sample:
   //
   //---------------------------------------------
   // Library Linkage
   //---------------------------------------------
   //-
   #if defined (_DEBUG)
   #pragma comment( lib, "lua.lib" ) // Lua Support
   #else
   #pragma comment( lib, "lua.lib" ) // Lua Support
   #endif
   //-

   Remember: To change your Project Property -> linker -> general -> additional library directory: lua lib directory.

3. Add Lua include files:
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   extern "C" 
   {
   #include <span class="code-string">"lua.h"
   </span>
   }

   Remember: To change your Project Property -> C/C++ -> general -> additional include directories: lua include directory.

   Notice that all the files in lua lib need to stay with "c" extension, because Lua was written to be ANSI C compliant.

4. Now we need to start Lua VM as follows:
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   LRESULT OnCreate(UINT 
   /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& 
   /*bHandled*/)
   {
   //...
   // Lua
   //
   lua_State *luaVM = lua_open(); /* 
   Open Lua */
   //
   luaopen_base(luaVM );     /* opens the 
   basic library */
   luaopen_table(luaVM );    /* opens the table 
   library */
   luaopen_io(luaVM );       /* opens 
   the I/O library */
   luaopen_string(luaVM );   /* opens the string 
   lib. */
   luaopen_math(luaVM );     /* opens the math lib. 
   */
   if (NULL == 
   luaVM)
   {
            
   MessageBox("Error Initializing lua\n");
   }
   //...
   // Do things with lua 
   code.
   // see below
   //...
   lua_close(luaVM); /* Close Lua */
   //
   // 
   End
   //...
   }

5. Now we make a glue function of Lua and C/C++.

   The Lua API function to do this is:

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   lua_register(s, n, g)

   where

   • s: is the lua_State to register the function.
   • n: is the name of the function exposed to Lua.
   • g: the C/C++ glue function.

   See the sample:

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   //...
   // Do things with 
   lua code.
   lua_register( luaVM, "SetHome", l_SetHome );
   //...
   // 
   -------------------------------------------
   // 
   #Lua Functions
   // 
   ------------------------------------------
   //
   static 
   int l_SetTitle( lua_State* 
   luaVM)
   {
            const char* 
   title = luaL_checkstring(luaVM, 
   1);
            
   theMainFrame->SetWindowText(title);
            
   return 0;
   }

6. Now we need the load and execute Lua scripts:
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   //...
   // Do things with lua 
   code.
   lua_register( luaVM, "SetHome", l_SetHome );
   //more glue 
   functions
   lua_dofile(luaVM, "hrconf.lua");
   //...

   The Lua API function to do this is:

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   lua_dofile(s, p)

   where

   • s: is the lua_State to register the function.
   • p: path for Lua script file.

   See the demo script.

4

• Lua is a free software.
• Download Lua: Download.
• Manual: Reference manual for Lua 5.0.
• References: Lua.

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